The use of trailers in the transportation and launching of boats and other small watercraft is well known. Conventional boat trailers consist of a wheel supported metal frame upon which a crib or boat bunk is mounted to support the boat hull. Conventional trailers are provided with a hitch coupling at a front end which permits the trailer to be secured to a vehicle-mounted trailer hitch for transport. In launching a boat, with the hitch coupling secured to a vehicle, the rear end of the trailer is backed down a public or marina ramp until the boat bunk is submerged to a sufficient extent that the boat can be floated clear of the trailer. The empty trailer is then pulled from the lake and must be stored until such time as the boat is to be retrieved for transport elsewhere.
In addition to the expense and inconvenience of storage, conventional boat trailers suffer a disadvantage in that the combined weight of the boat and trailer typically necessitates that only larger vehicles, such as pick-up trucks or sport utility vehicles, may be used to transport and launch the boat from the trailer.
In addition, if the launch ramp is privately owned, users may be liable to pay launch fees for its use. Public launch ramps are frequently inconveniently located, requiring that the boat be driven up to tens of miles to and from the boat launch site to its mooring. As a practical matter, when small watercraft and boats are moored at a dock, it often is not possible to safely pilot the watercraft over long distances to a public launch ramp for removal and sheltering during sudden storms.
In an effort to overcome at least some of the disadvantages associated with conventional boat trailers, various individuals have proposed boat railway systems which are designed to enable individuals to remove boats from lakes and rivers without the difficulties associated with trailers. Boat railway systems are unsightly, however, and involve the laying of parallel steel railroad rails on sleepers from a user's boat house a distance into the lake or river. Boats are raised and lowered from the lake by positioning the boat onto a wheeled sled and winching the sled along the rails. Railway systems are quite expensive and may cost thousands of dollars. In addition, if the railways are not removed from northern lakes and rivers each winter, they may be susceptible to ice damage and fouling by sedimentation. Permanent railway systems also require relatively constant water levels and may also be prohibited by building or environmental restrictions, or even bottom or surf conditions.